Manufacture of wire links for tension members of bridges, &amp;c.



No. 678,672. Patentedduly I6, 1904. ENTHAL.

TENSION MEMBERS OF BRIDGES, &c.

on filed Apr. 12, 1901.)

llllll --Sheet I.

(No Model.) 3 S MANUFACTURE OF WIRE LINKS (Applicat No. 678,672. Patented .luly l6, l90l. G. LINDENTHAL.

MANUFACTURE OF WIRE LINKS FOB TENSION MEMBERS OF BRIDGES, 8w. (Application filed Apr. 12} mm.

(No Model.) 3 Sheets-8heet 3.

hllTElD Stamps eUsrAv LINDENTHAL,

Arrest rricn;

OF NEW YORK, N. Y.

SPECIFICATION forming part of Letters Eatent No. 678,672, dated July 16, 19 01. Original application filed June 28, 1897', Serial No; 642,678. Divided and this application filed April 12, 1901. Serial To aZZ whom it may concern:

Be it known that I, GUSTAV LINDENTHAL, a citizen of the United States, and a resident of the city, county, and State of New York, have invented certain new and useful Improvements in the Manufacture of WVire Links for Tension Members in Bridges and other Similar Structures, of which the following is a full, clear, and exact specification.

WVire links for tension members in bridges and other similar structures produced by the processes heretofore in use-nainely, by wind ing the wire around shoes or half-round bearings at each end of the link-are defective in that in the resulting product the Wires are not under equal tension, the inner wires being less strained than the outer ones, because the wires when bent aroundthe shoes or bearings are subjected to a severe tension, and the accumulating tension from the wires as they are wound layer after layer around the shoes or bearings produces a cumulative compression of the frame or brace between the shoes, as a result of which the inner layers of the wire coil become somewhat relaxed. Thus the outer and inner layers of wire are not equally strained any longer, although uniform tension has been maintained in the wires during the process of winding. When such links are used in the construction of a bridge or similar structure, overstrainin g and eventually breaking of the outer layer of wires is the result.

The object of my invention is to devise a process of manufacture of wire links wherein all strands or wires are equally strained, each wire having the same tension as any other wire in the same link.

Myimproved process consists,tlrst, of winding the wires or strands into a circular coil upon a frame, supporting the wires in nu merous intermediate points, without strain except as may be necessary to prevent looseness in the laying of the wires; second, shaping the coil thus produced into a link by gradually flattening the coil and then bending the strands or wires at the ends or heads of the link by compressing them upon the shoes; third, stretching the link by applying between the heads thereof a pressure equal to the aggregate tension of all wires contained (No model) in the link as calculated for each wire, and,

fourth, fixing the link while thus stretched plication for Letters Patent filed June 28,

1897, Serial No. 642,678, of which the present application is a subdivision, and consisting of awinding-reel adjustable as to diameter, a device for regulating and maintaining such slight tension upon the wires or strands during the winding as is required to prevent looseness of the wires, and of devices for shaping the coil produced by winding the wire upon the winding-reel into a link.

The successive steps of the process of manufacture of wire links for bridges and similar structures according to my invention are illustrated in the accompanying drawings, wherein Figure 1 is an elevation of a circular coil of wire A, the strands thereof being secured by temporary lashings a, and the shoes B being secured thereto in two points diametrically opposite each other; also, by temporary lashings b. Fig. 2 is a similar view of the coil of wire partly flattened. Fig. 3 is an elevation showing the coil of wire as it appears in the next period of the process, wherein the strands are pressed parallel to each other. Fig. 4 is an elevation of the link, showing the strands of the coil compressed in the bearings of the shoes; and Fig. 5 is an elevation of the link in finished state and provided with permanent lashings O.

The wire used in the manufacture of such links is steel wire, either round or square in sectional area, and is obtained from wiremills wound in coils of certain weight. Before winding it on the reel, so as to produce the coil whereof the link is thereafter shaped, this wire must first be unwound and straightened in suitable machines and the ends of 'as many coils spliced together as maybe necessary to produce one continuous strand or wire for one link. The wire thus prepared is wound upon an ordidary wire-reel of sufficient size to prevent a permanent set or bend in the wire. The end of the Wire is then drawn through a tension device and fastened to one of the shoes attached to the arms of the winding-reel. The tension device is then adjusted to hold the wire with just force enough to keep it in its proper place upon the windingreel and to prevent any looseness of the wire in the coil. lfround wire is used in the manufacture of such links, bearing strips described in my United States Patent No. 608,690, dated August 9, 1898, are secured in position upon the shoes in the manner explained therein. These bearing-strips are slightly bent on their ends, so as.not to interfere with the winding of the wire and lubricated to facilitate the gliding of the wires thereon during the subsequent operations when the coil is being shaped into a link. When square or fiat wires are used in the manufacture of the links, no such bearing-strips are required. WVhen the winding is finished, the wires are tied together by temporary lashings at suitable intervals and the shoes secured to the coil also by temporary lashings. The coil is released from the reel by detaching the shoes from the arms and by drawing together or loosenening the adjustable arms of the reel. The coil when removed from the reel is circular in shape. It is then brought into suitable position to be flattened into the form of the link by hydraulic rams applied either inside the ring between the shoes or outside the ring for compresing it sidewise, or by a combination of both operations. This condition of the coil when the strands are nearly straight and approximately parallel to each other on both sides of the shoes is shown in Fig. 8 of the drawings forming part of my aforesaid application. When the link is formed into the shape explained above, the ends or heads thereof are. compressed between the jaws of a hydraulic vise, whose gripping-faces conform to the shape of the heads of the link, whereby the wires are pressed into their proper bearings around the shoes. By this operation, also, the bearing-strips, if any are used, are bent into conformity with the heads of the link, and the wires and bearing-strips are forced into the grooves between the flanges of the shoes and com pressed therein. Next clamps or wire lashings are placed around both strands of the link close to the shoes, and then the link is subjected to a stretching operation by means of a hydraulic ram operating against the shoes thereof. The object of this operation is to put the wire of the link under a certain predetermined tension, uniform on all wires, during which tension the boring out of the shoes to the exact.

length of the link may take place, or another method is to mark the exact and required length upon the shoes While the link is under the described tension and bore out the accurate bearings after the link is released from tension. The total tension put upon each link during this stretching process is calculated from the number of wires in the link. For instance, if the link is made of one hun dred turns of wire and each wire calculated to bear a tension of four hundred pounds then the total pressure to be applied between the shoes during the stretching operation will be 200 400=80,000 pounds. If the link is composed of only one hundred and sixty wires, (eighty turns,) then the total pressure between the shoes during the boring operation will be only 160 400:64,000 pounds. After the link is finished to its exact length temporary lashings, as many as may be required, are placed around it at short intervals, and after such oiling or painting as may be required the link is boxed to protect it during transportation.

The diameter of the winding-reel represented by the arms supporting the shoes, saddles, and .reeds during the process of winding is calculated so that the flattened coil Will have exactly the desired length of the link.

I claim as my invention= 1. A process of manufacture of wire links for tension members of bridges and similar structures consisting of the following steps: first, Winding a circular coil of wire, binding the wires of the coil together with temporary lashings and securing to the coil of shoes or bearing-saddles on two diametrically opposite points; second,- shaping the link by fiattening the coil between the points where the shoes or bearing-sad dles are secured to it, and by compressing the strands of the coil upon the bearing-surfaces of the shoes or hearing saddles; third, stretching the link under tension before finishing it to its exact length.

2. A process of manufacture of wire links for tension members of bridges and similar structures consisting of the following steps: first, winding the wire into a circular coil while stretching it only to such tension as maybe necessary to keep the successive turns of the wire in position; second, binding the strands of the coil together with temporary lashes and securing tothe coil of shoes or bearing-saddles on two diametrically opposite points; third, shaping the coil by driving apart the points where the shoes or bearingsaddles are secured thereto; fourth, compressing the strands of the coil upon the bearingsurfaces of the shoes or bearing-saddles; and,

fifth, stretching the link under tension before finishing the link to its exact length.

GUSTAV LINDENTHAL.

WVitnesses:

ROBERT VALENTINE MATHEWs, JOHN A. PAULSON. 

